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151.
用Na_2CO_3作为助溶剂、Na_2O_2作为消解剂,采用微波焙烧法和马弗炉焙烧法消解处理废钒钨钛脱硝催化剂。通过XRF、BET、XRD和NH_3-TPD技术对两种消解方法制得的钛钨粉样品进行了表征。表征结果显示,与马弗炉焙烧法相比,微波焙烧法得到的钛钨粉纯度更高,TiO_2与WO_3含量之和大于96.7%(w),且该钛钨粉还具有更高的比表面积和酸性,可以作为钒钨钛脱硝催化剂的生产原料再利用。  相似文献   
152.
The term ‘indicator’ is often vague and heterogeneous, and its dynamic characteristics make it highly variable over time and space. Based on reviews and synthesis, this study visualizes phenomena and highlights the trend of indicator selection criteria, development methods, validation evaluation strategies for improvement. In contextualization of the intensification of agriculture and climate change, we proposed a set of indicators for assessing agricultural sustainability in Bangladesh based on theoretically proposed and practically applied indicators by researchers. Also, this article raises several issues of indicator system development and presents a summary after due consideration. Finally, we underline multi-stakeholders’ participation in agricultural sustainability assessment.  相似文献   
153.
噪声治理技术实例研究   总被引:1,自引:0,他引:1  
文章从噪声源入手,分析泵房和压缩机房内的噪声对工作人员和居民不同程度的影响和危害,按照噪声控制的原理,采取吸声、隔声、消声相结合的降噪措施。治理后,泵房、压缩机房内噪声值低于85 dB(A),压缩机房厂界噪声值低于60 dB(A),居民楼外1 m处的噪声值低于45 dB(A),有效减少噪声对作业场所和周边环境的污染。  相似文献   
154.
Thuan NT  Tsai CL  Weng YM  Lee TY  Chang MB 《Chemosphere》2011,83(6):760-766
Twenty-one fresh water samples were taken from reservoirs, wells and drinking water treatment plants in Taiwan for measurement of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) concentrations. Due to low concentration of PCDD/Fs, water samples (400-1000 L) were collected by using the on-site large volume pre-concentration system and analyzed by high resolution gas chromatography (HRGC)/high resolution mass spectrometer (HRMS). Different characteristics of dioxin profiles in surface water and groundwater are observed. The PCDD/F concentrations in fresh water samples varied from 0.001 to 0.265 pg WHO98-TEQ/L which are lower than the standard (12 pg WHO98-TEQ/L) set by the Taiwan Environmental Protection Administration (TEPA) for drinking water. Only a small fraction (<5%) of the total PCDD/F concentration in fresh water samples was water-soluble. As a result of their hydrophobicity, PCDD/Fs are effectively removed along with suspended solid via the water treatment process (average 98% removal efficiency).  相似文献   
155.
In order to develop a sound material-cycle society, cost-effective municipal solid waste (MSW) management systems are required for the municipalities in the context of the integrated accounting system for MSW management. Firstly, this paper attempts to establish an integrated cost-benefit analysis (CBA) framework for evaluating the effectiveness of MSW management systems. In this paper, detailed cost/benefit items due to waste problems are particularly clarified. The stakeholders of MSW management systems, including the decision-makers of the municipalities and the citizens, are expected to reconsider the waste problems in depth and thus take wise actions with the aid of the proposed CBA framework. Secondly, focusing on the financial cost, this study develops a generalized methodology to evaluate the financial cost-effectiveness of MSW management systems, simultaneously considering the treatment technological levels and policy effects. The impacts of the influencing factors on the annual total and average financial MSW operation and maintenance (O&M) costs are analyzed in the Taiwanese case study with a demonstrative short-term future projection of the financial costs under scenario analysis. The established methodology would contribute to the evaluation of the current policy measures and to the modification of the policy design for the municipalities.  相似文献   
156.
近年来,SiC材料作为一种新型的柴油车尾气颗粒物过滤材料获得了迅速发展,正逐步取代目前广泛应用的堇青石多孔陶瓷材料.结合堇青石和SiC过滤材料的性能特点,重点概述了2种SiC改性过滤材料(重结晶SiC.RSiC和硅结合SiC,Si-SiC)的研究和应用进展,并介绍了SiC颗粒物过滤器的市场现状和发展前景.  相似文献   
157.
对平果热电厂皮带上煤除尘系统失效进行了故障诊断 ,对故障产生的主要原因诱导风流进行了详细的分析 ,采取了可行的改进措施  相似文献   
158.
Natural gas industry is developing rapidly, and its accidents are threatening the urban safety. Risk management through quantitative assessment has become an important way to improve the safety performance of the natural gas supply system. In this paper, an integrated quantitative risk analysis method for natural gas pipeline network is proposed. This method is composed of the probability assessment of accidents, the analysis of consequences and the evaluation of risk. It is noteworthy that the consequences analyzed here include those of the outside and inside gas pipelines. The analysis of consequences of the outside pipelines focuses on the individual risk and societal risk caused by different accidents, while those of the inside pipelines concerns about the risk of the economic loss because of the pressure re-distribution. Risk of a sample urban gas pipeline network is analyzed to demonstrate the presented method. The results show that this presented integrated quantitative risk analysis method for natural gas pipeline network can be used in practical application.  相似文献   
159.
采用水培的方法,研究了不同硫素供应水平对铜镉复合胁迫(Cu+Cd:10μmol·L-1+10μmol·L-1)下,小麦幼苗铜镉吸收、亚细胞分布及生理毒性的影响.结果表明,缺硫和高硫处理均降低了小麦幼苗根系和叶片中铜和镉的含量,不同硫水平处理对小麦幼苗根系亚细胞各组分中镉的分配比例没有产生影响,而对铜亚细胞组分的分配比例...  相似文献   
160.
Iodine, as one of the essential trace elements for human body, is very important for the proper function of thyroid gland. In some regions, people are still suffering from iodine deficiency disorder (IDD). How to provide an effective and cost-efficient iodine supplementation has been a public health issue for many countries. In this review, a novel iodine supplementation approach is introduced. Different from traditional iodine salt supplement, this approach innovatively uses cultivated iodine-rich phytogenic food as the supplement. These foods are cultivated using alga-based organic iodine fertilizer. The feasibility, mechanics of iodine absorption of plants from soil and the bioavailability of iodine-rich phytogenic food are further discussed.  相似文献   
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